1 /*
2 * Copyright (C) 2016 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 #include "Driver.h"
18
19 #include <err.h>
20 #include <string.h>
21
22 #include <chrono>
23 #include <mutex>
24 #include <string>
25 #include <thread>
26 #include <unordered_map>
27 #include <vector>
28
29 #include <clang/AST/ASTConsumer.h>
30 #include <clang/Basic/Diagnostic.h>
31 #include <clang/Basic/TargetInfo.h>
32 #include <clang/Basic/VirtualFileSystem.h>
33 #include <clang/Driver/Compilation.h>
34 #include <clang/Driver/Driver.h>
35 #include <clang/Frontend/CompilerInstance.h>
36 #include <clang/Frontend/CompilerInvocation.h>
37 #include <clang/Frontend/FrontendAction.h>
38 #include <clang/Frontend/FrontendActions.h>
39 #include <clang/Frontend/TextDiagnosticPrinter.h>
40 #include <clang/Frontend/Utils.h>
41 #include <clang/FrontendTool/Utils.h>
42 #include <llvm/ADT/IntrusiveRefCntPtr.h>
43 #include <llvm/ADT/SmallVector.h>
44 #include <llvm/ADT/StringRef.h>
45 #include <llvm/Config/config.h>
46
47 #include "Arch.h"
48 #include "DeclarationDatabase.h"
49 #include "versioner.h"
50
51 using namespace std::chrono_literals;
52 using namespace std::string_literals;
53
54 using namespace clang;
55
56 class VersionerASTConsumer : public clang::ASTConsumer {
57 public:
58 HeaderDatabase* header_database;
59 CompilationType type;
60
VersionerASTConsumer(HeaderDatabase * header_database,CompilationType type)61 VersionerASTConsumer(HeaderDatabase* header_database, CompilationType type)
62 : header_database(header_database), type(type) {
63 }
64
HandleTranslationUnit(ASTContext & ctx)65 virtual void HandleTranslationUnit(ASTContext& ctx) override {
66 header_database->parseAST(type, ctx);
67 }
68 };
69
70 class VersionerASTAction : public clang::ASTFrontendAction {
71 public:
72 HeaderDatabase* header_database;
73 CompilationType type;
74
VersionerASTAction(HeaderDatabase * header_database,CompilationType type)75 VersionerASTAction(HeaderDatabase* header_database, CompilationType type)
76 : header_database(header_database), type(type) {
77 }
78
CreateASTConsumer(CompilerInstance &,llvm::StringRef)79 std::unique_ptr<ASTConsumer> CreateASTConsumer(CompilerInstance&, llvm::StringRef) override {
80 return std::make_unique<VersionerASTConsumer>(header_database, type);
81 }
82 };
83
constructDiags()84 static IntrusiveRefCntPtr<DiagnosticsEngine> constructDiags() {
85 IntrusiveRefCntPtr<DiagnosticOptions> diag_opts(new DiagnosticOptions());
86 auto diag_printer = std::make_unique<TextDiagnosticPrinter>(llvm::errs(), diag_opts.get());
87 IntrusiveRefCntPtr<DiagnosticIDs> diag_ids(new DiagnosticIDs());
88 IntrusiveRefCntPtr<DiagnosticsEngine> diags(
89 new DiagnosticsEngine(diag_ids.get(), diag_opts.get(), diag_printer.release()));
90 return diags;
91 }
92
93 // clang's driver is slow compared to the work it performs to compile our headers.
94 // Run it once to generate flags for each target, and memoize the results.
95 static std::unordered_map<CompilationType, std::vector<std::string>> cc1_flags;
96 static const char* filename_placeholder = "__VERSIONER_PLACEHOLDER__";
generateTargetCC1Flags(llvm::IntrusiveRefCntPtr<clang::vfs::FileSystem> vfs,CompilationType type,const std::vector<std::string> & include_dirs)97 static void generateTargetCC1Flags(llvm::IntrusiveRefCntPtr<clang::vfs::FileSystem> vfs,
98 CompilationType type,
99 const std::vector<std::string>& include_dirs) {
100 std::vector<std::string> cmd = { "versioner" };
101 cmd.push_back("-std=c11");
102 cmd.push_back("-x");
103 cmd.push_back("c-header");
104 cmd.push_back("-fsyntax-only");
105
106 cmd.push_back("-Wall");
107 cmd.push_back("-Wextra");
108 cmd.push_back("-Werror");
109 cmd.push_back("-Wundef");
110 cmd.push_back("-Wno-unused-macros");
111 cmd.push_back("-Wno-unused-function");
112 cmd.push_back("-Wno-unused-variable");
113 cmd.push_back("-Wno-unknown-attributes");
114 cmd.push_back("-Wno-pragma-once-outside-header");
115
116 cmd.push_back("-target");
117 cmd.push_back(arch_targets[type.arch]);
118
119 cmd.push_back("-DANDROID");
120 cmd.push_back("-D__ANDROID_API__="s + std::to_string(type.api_level));
121 cmd.push_back("-D_FORTIFY_SOURCE=2");
122 cmd.push_back("-D_GNU_SOURCE");
123 cmd.push_back("-D_FILE_OFFSET_BITS="s + std::to_string(type.file_offset_bits));
124
125 cmd.push_back("-nostdinc");
126
127 if (add_include) {
128 cmd.push_back("-include");
129 cmd.push_back("android/versioning.h");
130 }
131
132 for (const auto& dir : include_dirs) {
133 cmd.push_back("-isystem");
134 cmd.push_back(dir);
135 }
136
137 cmd.push_back(filename_placeholder);
138
139 auto diags = constructDiags();
140 driver::Driver driver("versioner", llvm::sys::getDefaultTargetTriple(), *diags, vfs);
141 driver.setCheckInputsExist(false);
142
143 llvm::SmallVector<const char*, 32> driver_args;
144 for (const std::string& str : cmd) {
145 driver_args.push_back(str.c_str());
146 }
147
148 std::unique_ptr<driver::Compilation> Compilation(driver.BuildCompilation(driver_args));
149 const driver::JobList& jobs = Compilation->getJobs();
150 if (jobs.size() != 1) {
151 errx(1, "driver returned %zu jobs for %s", jobs.size(), to_string(type).c_str());
152 }
153
154 const driver::Command& driver_cmd = llvm::cast<driver::Command>(*jobs.begin());
155 const driver::ArgStringList& cc_args = driver_cmd.getArguments();
156
157 if (cc_args.size() == 0) {
158 errx(1, "driver returned empty command for %s", to_string(type).c_str());
159 }
160
161 std::vector<std::string> result(cc_args.begin(), cc_args.end());
162
163 {
164 static std::mutex cc1_init_mutex;
165 std::unique_lock<std::mutex> lock(cc1_init_mutex);
166 if (cc1_flags.count(type) > 0) {
167 errx(1, "attemped to generate cc1 flags for existing CompilationType %s",
168 to_string(type).c_str());
169 }
170
171 cc1_flags.emplace(std::make_pair(type, std::move(result)));
172 }
173 }
174
getCC1Command(CompilationType type,const std::string & filename)175 static std::vector<const char*> getCC1Command(CompilationType type, const std::string& filename) {
176 const auto& target_flag_it = cc1_flags.find(type);
177 if (target_flag_it == cc1_flags.end()) {
178 errx(1, "failed to find target flags for CompilationType %s", to_string(type).c_str());
179 }
180
181 std::vector<const char*> result;
182 for (const std::string& flag : target_flag_it->second) {
183 if (flag == "-disable-free") {
184 continue;
185 } else if (flag == filename_placeholder) {
186 result.push_back(filename.c_str());
187 } else {
188 result.push_back(flag.c_str());
189 }
190 }
191 return result;
192 }
193
initializeTargetCC1FlagCache(llvm::IntrusiveRefCntPtr<clang::vfs::FileSystem> vfs,const std::set<CompilationType> & types,const std::unordered_map<Arch,CompilationRequirements> & reqs)194 void initializeTargetCC1FlagCache(llvm::IntrusiveRefCntPtr<clang::vfs::FileSystem> vfs,
195 const std::set<CompilationType>& types,
196 const std::unordered_map<Arch, CompilationRequirements>& reqs) {
197 if (!cc1_flags.empty()) {
198 errx(1, "reinitializing target CC1 flag cache?");
199 }
200
201 auto start = std::chrono::high_resolution_clock::now();
202 std::vector<std::thread> threads;
203 for (const CompilationType type : types) {
204 threads.emplace_back([type, &vfs, &reqs]() {
205 const auto& arch_req_it = reqs.find(type.arch);
206 if (arch_req_it == reqs.end()) {
207 errx(1, "CompilationRequirement map missing entry for CompilationType %s",
208 to_string(type).c_str());
209 }
210
211 generateTargetCC1Flags(vfs, type, arch_req_it->second.dependencies);
212 });
213 }
214 for (auto& thread : threads) {
215 thread.join();
216 }
217 auto end = std::chrono::high_resolution_clock::now();
218
219 if (verbose) {
220 auto diff = (end - start) / 1.0ms;
221 printf("Generated compiler flags for %zu targets in %0.2Lfms\n", types.size(), diff);
222 }
223
224 if (cc1_flags.empty()) {
225 errx(1, "failed to initialize target CC1 flag cache");
226 }
227 }
228
compileHeader(llvm::IntrusiveRefCntPtr<clang::vfs::FileSystem> vfs,HeaderDatabase * header_database,CompilationType type,const std::string & filename)229 void compileHeader(llvm::IntrusiveRefCntPtr<clang::vfs::FileSystem> vfs,
230 HeaderDatabase* header_database, CompilationType type,
231 const std::string& filename) {
232 auto diags = constructDiags();
233 std::vector<const char*> cc1_flags = getCC1Command(type, filename);
234 auto invocation = std::make_unique<CompilerInvocation>();
235 if (!CompilerInvocation::CreateFromArgs(*invocation.get(), &cc1_flags.front(),
236 &cc1_flags.front() + cc1_flags.size(), *diags)) {
237 errx(1, "failed to create CompilerInvocation");
238 }
239
240 clang::CompilerInstance Compiler;
241
242 // Remove the workaround once b/35936936 is fixed.
243 #if LLVM_VERSION_MAJOR >= 5
244 Compiler.setInvocation(std::move(invocation));
245 #else
246 Compiler.setInvocation(invocation.release());
247 #endif
248
249 Compiler.setDiagnostics(diags.get());
250 Compiler.setVirtualFileSystem(vfs);
251
252 VersionerASTAction versioner_action(header_database, type);
253 if (!Compiler.ExecuteAction(versioner_action)) {
254 errx(1, "compilation generated warnings or errors");
255 }
256
257 if (diags->getNumWarnings() || diags->hasErrorOccurred()) {
258 errx(1, "compilation generated warnings or errors");
259 }
260 }
261